1. Field of the Invention
The present invention relates to clamps generally, and more particularly, relates to a locking manual hold down clamp.
2. Description of Related Art
Toggle and hold down clamps have been used and known in the art for many years. A typical hold down or toggle clamp includes a clamping arm which pivots between a released and clamped position. The clamps are used to hold work pieces in place for processing, for clamping two objects to one another, or for clamping an object to a work table or other surface. Toggle and hold down clamps generally are quickly engageable and disengageable to the work piece or object being held. They also provide a considerable holding and clamping force which enables them to hold the work piece or object securely where needed.
Many of these prior art devices hold the clamp position to a variety of means, these means include maintaining the force applied to the bar or arm of the clamp. Other prior art clamps create a holding force by passing the links of the toggle clamps to an over center position, the over center position subjects the links and the pivot points of the clamp to very high loads resulting in increased wear and potential deformation of the clamp components thereby reducing the life of the clamp.
There have been some problems with some prior art clamps releasing due to vibration and other unforeseen forces during the use of the clamps. Some of these prior art clamps include several bends in their links and power arms. These bends may reduce performance and strength of the clamp by amounts up to 30 to 40 percent. Some of these clamps also include parts that have bends that are not interchangeable and have to be put together in precise positions, thus increasing the cost of labor of assembling the clamps. Also many of these prior art clamps do not include a positive locking mechanism which will ensure the clamp is locked and not capable of being opened when it is in its fully engaged position. The positive locking of the clamp is necessary in manufacturing environments where the unexpected disengagement of a clamp may produce hazards and other down time on manufacturing lines because of such unexpected releases.
Therefore, there is a need in the art for an improved locking hold down action clamp that is more robust, has greater strength and interchangeability than prior art clamps. There also is a need in the art for a locking clamp that has a positive lock that will only disengage upon user interaction with the locking mechanism of the clamp.